RU2238695C1 - Method for manufacturing composite grid crown - Google Patents

Abstract

FIELD: medical engineering.

SUBSTANCE: method involves odontic preparation of tooth stump for giving to it cylindrical shape and forming steps at the level of gingival on vestibular and oral surface and retention places like 0.2-0.3 mm deep horizontal grooves. Stump tissue filing depth is equal to 0.9-1.2 mm. Crown carcass formation is carried out corresponding to preliminarily produced gypsum model of the formed stump. The carcass is manufactured from gold-coated metal wire with cell thickness of 0.4 mm. The carcass is mounted on gypsum model and is twice covered with masking agent before the crown part is repaired/restored by coating the carcass with composite material. Anatomical form of grid crown part is corrected and fixed on the stump with cement.

EFFECT: full-scale repair of anatomical form and functions of injured tooth; long service life of crown part.

Description

The invention relates to medicine, namely to dentistry, to a method for manufacturing a mesh-composite crown with defects in the crown of the tooth.

The causes of damage to the hard tissues of the tooth include: caries and its complications, pathological abrasion, acute and chronic trauma. As therapeutic agents for defects in the crown of the tooth, mainly prostheses are used: inlays and artificial crowns [2-3, 5, 8-12]. The tab is a fixed microprosthesis of a part of a tooth crown. It is used to restore the anatomical shape of the tooth. Currently, there are several types of tabs: all-ceramic, composite, metal, combined, IPS Impress tabs, Seges computer tabs [4, 6, 7]. A crown is a fixed prosthesis that fully restores the anatomical shape, function and appearance of a damaged tooth. Depending on the material, crowns are distinguished: metal (alloys of noble and base metals), non-metal (plastic, porcelain), combined (metal (lined with plastic or porcelain). Crowns are a more traditional and affordable, rational and effective method of repairing defects of the dentition, compared to the tabs.

The crown allows you to:

• Repair a damaged tooth.

• Protect loose or split teeth from further decay.

• Correct irregular shape and discolored tooth.

• Strengthen the rest of the tooth when this cannot be achieved by filling or using the tab.

• Be a support for the bridge.

The closest in technical essence is taken as a prototype ceramic lining of the framework of the chewing teeth according to Kuwata [1].

Disadvantages of ceramic-metal crowns:

1. The impossibility of prosthetics with small sizes of crowns in the vestibulooral and mesiodistal directions, in particular the lower incisors.

2. The impossibility of prosthetics with low clinical crowns.

3. The inability to use with malocclusion (deep incisal overlap).

4. Inability to use in children.

5. The inability to use in people with periodontal disease, bruxism, epilepsy.

6. The need to prepare a large number of hard tissues of the tooth (1.5-2.0 mm).

7. High probability of thermal burn of the pulp.

8. The need to use a retraction thread.

9. The need for tooth removal in case of tilt.

10. The complexity of odontopreparation (creating a step, the taper of the walls is not more than 10-15%).

11. The need to manufacture a temporary (provisional) crown on the prepared tooth.

12. A complex, multi-stage manufacturing process.

13. Difficulties in simulating tooth transparency.

14. Color change due to metal frame.

15. Duration of manufacture (requires several visits).

16. The difficulty of fixing.

17. During cementing of the prosthesis, an increased hydraulic pressure of the cement is created inside the crown.

18. Penetration of fixing cement into the gingival fissure.

19. There is no way to correct the color.

20. Increased tooth abrasion of antagonists due to the more pronounced hardness of ceramics, compared with tooth enamel.

21. Functional overload of periodontal.

22. Causes inflammatory changes in the gums.

23. Frequent chips of ceramic cladding.

24. Possible out-of-alignment of crowns.

25. If necessary, endodontic treatment is necessary to remove the crown.

26. High cost.

The aim of this invention is the full restoration of the anatomical shape, functions and appearance of the damaged tooth, the prevention of chips and chips, increasing the durability of the crown of the tooth along with high aesthetics.

Advantages of a mesh-composite crown:

1. A gentle method of preparation.

2. The crown does not injure periodontal tissues.

3. The ability to carry out the laboratory phase as a doctor and dental technician.

4. Low cost.

5. The ease of construction.

6. Mesh-composite crown is made quickly and predictably.

7. Low cost.

8. The mesh frame provides high strength crowns.

9. A simplified method of manufacturing a crown .;

10. Lightweight robust design.

11. Eliminates the process of casting the frame.

12. Accelerates the recovery period of the defect.

13. Reduces time costs.

14. Increases the economic effect.

15. The mesh frame due to the cellular structure provides a full fixation of the structure.

16. The mesh frame, connecting with the composite material, forms a single monoblock, providing structural strength.

17. The mesh structure of the mesh provides a solid connection of the portions of the composite with each other and prevents chips and chips.

18. Double adhesive and camouflage treatment of the mesh frame not only improves the strength of the connection with the composite, but also eliminates the change in color of the crown.

19. The mesh frame in combination with modern adhesive composite materials creates a monoblock - a multilayer reinforced structure without its inherent weak boundaries between the layers, which ensures the reliability and effectiveness of the crown.

20. The mesh-composite crown is an alternative to metal, non-metallic and combined crowns.

21. The mesh frame expands the possibility of modeling the crown of the tooth.

22. The mesh frame allows you to restore the coronal part of the tooth in the simplest way.

23. The mesh structure of the mesh frame provides retention and aesthetic effect.

24. The ability to create access through perforation without removing the crown, if necessary, endodontic intervention.

25. The ability to remove easily and quickly mesh-composite crown if necessary.

26. Gold-plated mesh frame provides a shade similar to dentin.

27. The yellow color of the metal mesh in the composite layer is less visible and looks more natural and provides a natural appearance of the crown.

28. Gold-plated mesh frame is not only aesthetic, but also compatible with composite and tooth tissues.

29. Many colors of the composite contribute to the achievement of maximum aesthetic results.

30. The gold-plated mesh frame not only increases the area of contact with the composite, but also provides 95% crown reinforcement.

31. Gold-plated mesh frame helps to reduce shrinkage of the composite material and leads to an improvement in the marginal fit of the composite to the hard tissues of the tooth.

32. Gold-plated helps to reduce the stress (stress) that occurs during polymerization.

33. The mesh-composite crown provides the prevention of possible complications of chips and spalls and increases the longevity of the crown.

Grid-composite crown is made as follows.

Clinical Stage

1. Determination of the color of the crown.

2. Anesthesia.

3. Odontopreparation.

4. Imprinting.

Laboratory stage

1. Casting models.

2. Fixation of models in the occluder.

3. The formation of the mesh frame of the crown.

4. The manufacture of crowns.

5. Correction of the crown.

6. Grinding and polishing.

II Clinical Stage

1. Fitting the crown in the oral cavity.

2. Fixation of the crown.

Clinical and laboratory stages of manufacturing a mesh-composite crown.

I Clinical stage.

Removal of dental plaque and color determination.

Perform with pastes to remove dental plaque. A small amount of paste is applied to the tooth surface and brush and the tooth surface is cleaned at low revolutions of the drill motor to prevent injury to the gingival margin. After that, the teeth are thoroughly washed with a stream of water. To determine the color, use the standard VITA scale. Color matching is carried out in daylight. The patient should be in an upright position, the mouth should be at the eye level of the doctor, which is between the patient and the light source. Choose the color of the tooth body, then determine the shades needed to build the color composition of the tooth. For optimal color restoration of the natural appearance of the tooth, it is reproduced using composite materials of various shades and various degrees of transparency (more transparent - enamel and less transparent - opaque or dentine shades).

Anesthesia. Local anesthesia is performed to prevent possible pain.

Odontopreparation. Grinding of hard tooth tissues is carried out with diamond coated tools in combination with air-water cooling. They begin with the preparation of the masticatory surface using special barrel-shaped or spike-shaped diamond heads. The tops of the chewing tubercles are rounded. Next, the contact (approximate) surfaces are ground to the gums with a separation disk or cone-shaped boron. Boron is positioned so that the walls of the tooth are parallel, and the stump has a cylindrical shape. The preparation of the vestibular and oral surfaces is performed similarly to the contact, creating a ledge at the level of the gums. The thickness of the grinding of fabrics is 0.9-1.2 mm. To improve fixation on the tooth stump, retention points are formed in the form of horizontal furrows with a depth of about 0.2-0.3 mm.

Imprinting. Perform alginate mass. On both prints, the stump quality of the prepared tooth is evaluated. Next, casts are sterilized in an antiseptic solution.

Laboratory stage.

Casting models. A combined collapsible dentition model is cast. The auxiliary model is cast from gypsum, and the working one from super gypsum. Fold the models in a central occlusion and fix them in an occluder.

The formation of the mesh frame of the crown. To form a wireframe, a gold-plated metal mesh 0.4 mm thick by Renfert is used. A 2 × 2 cm square is cut out of the mesh, the corners and edges of which are cut with scissors and achieve a circle shape. Then, using a corkscrew, circles are cupped and tried on a plaster stump of the tooth. Then, with crampon and beak-shaped forceps, a mesh framework is formed in such a way that it matches the contours of the tooth stump. Then try on a frame on a plaster stump of the tooth.

Making a crown. The mesh frame is coated with adhesive, slightly blown with air for uniform distribution and polymerized by the standard method. Then a second layer of adhesive is applied and the manipulations are repeated. To improve the aesthetics of the crown, a masking agent is applied to the mesh frame, which is evenly, thinly distributed with a stream of air. Polymerized by the standard method. After which a masking agent is applied in a second layer, it is distributed and polymerized. The mesh-composite frame is mounted on a gypsum stump of the tooth. Next, the restoration / reconstruction of the crown of the tooth with composite materials is carried out according to the instructions.

Grinding, polishing. Use finishing burs for grinding, plastic and rubber heads, strips, soft flexible disks. For polishing, polishing pastes are used. A criterion for the quality of polishing is the appearance of a “dry" shine on all surfaces of the crown.

II Clinical stage.

Fitting and fixing the crown in the oral cavity. Before fitting, the crown is disinfected. After checking the quality of its fit, the crown is again disinfected, degreased and dried. Cement for fixing orthopedic crowns fill a third of the crown, smearing its walls. A crown is placed on the tooth and the patient is asked to close their teeth tightly. Excess hardened cement is removed after 10-15 minutes.

Clinical example.

The patient is 42 years old.

Complaints: aesthetic dissatisfaction with 34 teeth.

Anamnesis: Two years ago 34 teeth were covered with a stamped crown. Two weeks ago, the crown was unsealed.

Objectively: The coronal portion 34 of a tooth destroyed by _^1/2. Comparative percussion is painless.

Diagnosis: Defect of the crown of the 34 tooth.

Treatment: Mechanically, the surface of the teeth adjacent to the defect is cleaned with toothbrushes using toothpastes and a suitable color is determined according to the generally accepted VITA scale. A portion of the composite is applied to the tooth surface to refine and compare the selected color with the original.

Next, local anesthesia is performed to prevent possible pain.

Grinding of hard tooth tissues is carried out with diamond coated tools in combination with air-water cooling. They begin with the preparation of the chewing surface using special barrel-shaped diamond heads. The tops of the chewing tubercles are rounded.

Next, the contact (approximate) surfaces are ground to the gums with a separation disk or cone-shaped boron. Boron is positioned so that the walls of the tooth are parallel, and the stump has a cylindrical shape. The preparation of the vestibular and oral surfaces is performed similarly to the contact, creating a ledge at the level of the gums. The thickness of the grinding of fabrics is 0.9-1.2 mm. To improve fixation on the tooth stump, retention points are formed in the form of horizontal furrows with a depth of about 0.2-0.3 mm.

Impressions are made using alginate mass. Next, casts are sterilized in an antiseptic solution. A combined collapsible dentition model is cast. The auxiliary model is cast from gypsum, and the working one from super gypsum. Fold the models into a central occlusion and fix them in the occluder.

For the formation of the mesh frame using a gold-plated metal mesh with a thickness of 0.4 mm firm "Renfert". The metal mesh is designed to strengthen plastic prostheses (Catalog. Products for dental technicians 2001-2002, pp. 102-103). A square 2 × 2 cm is cut from the grid, the corners and edges of which are cut with scissors and achieve the shape of a circle. Then, with the help of a plug-in, the circles are cup-shaped and tried on a plaster stump of the tooth. Then, with crampon and beak-shaped forceps, a mesh framework is formed in such a way that it matches the contours of the tooth stump. Next, the mesh frame is removed from the gypsum model and coated with 3M ^ТМ SINGLE BOND DENTAL ADHESIVE SYSTEM adhesive (Catalog. Dental materials 2001. 3M Dental, page 6), slightly blown with air for uniform distribution and polymerized by the standard method. Then a second layer of adhesive is applied and the manipulations are repeated. To improve the aesthetics of a crown is applied to the grid frame masking agent - 3M ^{TM TM} RelyX CERAMIC PRIMER (Product Dental materials 2001. 3M Dental, p.11.) Which evenly distribute a thin layer of air. Polymerized by the standard method. Then a masking agent is applied in a second layer, it is distributed and polymerized. Then, the final restoration / reconstruction of the crown part of the tooth is carried out with composite materials for chewing groups of teeth - 3M ^ТМ FILTEK ^ТМ (Catalog. Dental materials 2001. 3М Dental). Correct the size, shape and occlusal surface of the crown.

Grind and polish the mesh-composite crown. Use finishing burs for grinding, plastic and rubber heads, strips, soft flexible disks. For polishing, polishing pastes are used.

Try and fix the crown in the oral cavity. Before fitting, the crown is disinfected. After checking the quality of its fit, the crown is again disinfected, degreased and dried. Cement for fixing orthopedic crowns fill a third of the crown, smearing its walls. A crown is placed on the tooth and the patient is asked to close their teeth tightly. Excess hardened cement is removed after 10-15 minutes.

The treatment by this method allows you to restore the anatomical shape, function and appearance of the damaged tooth. Complications with the above method were not identified.

Sources of information.

1. Kazunari Ohata. Ceramic lining of the framework of the chewing teeth according to Kuwata. Quintessence. 1991, No. 1. - S.53-65. Prototype.

2. Abolmasov N.G. Orthopedic dentistry Moscow: MEDpress-inform. 2002 .-- S.211-219.

3. Aparin V.V. Prevention of complications when using ceramic-metal prostheses. The journal "Dentistry". 1981, No. 2. - S. 34-36.

4. Unknown G.V. Long-term tab prosthetics results. The journal "Dentistry". 1990, No. 6. - S. 63-64.

5. Kopeikin V.N. Orthopedic dentistry. M. - 2000, S. - 156-165.

6. Petrosyan D.E. The use of ceramic inlays in restoring the occlusal surface of the teeth. The journal "Dentistry". 1997, No. 5. - S. 49-51.

7. Rogozhkina G.I. Restoration of hard tooth tissue inlays. NGMA - 2002. - P.40-51.

8. Ryakhovsky A.N. Edge fit - as a criterion for the quality of prosthetics with fixed prostheses. Magazine “Dental Technician” No. 3. 2000. - S.15-17.

9. Khudanogov G.N. Possibilities of using non-metallic ceramic dentures. New in dentistry. 1995, No. 2. - S.14-17.

10. Kristian W. New all-ceramic crowns and bridges - evaluation criterion. Quintessence. 1993 - 1994, No. 16-32.

11. Lothar Probster All-ceramic bridges: are they sufficiently tested in practice? Quintessence. 1993-1994, No. 32-39.

12. Iohn A. In - Ceram technology for manufacturing all-ceramic bridges. Quintessence. 1993-1994. - S. 39-74.

Claims (1)

A method of manufacturing a mesh-composite crown for defects in the crown of the tooth, including odontodiating the tooth stump to give it a cylindrical shape and forming ledges on the vestibular and oral surfaces and retention points in the form of horizontal grooves with a depth of about 0.2-0.3 mm, wherein the depth of grinding of the stump tissues is 0.9-1.2 mm, the formation of the crown frame in accordance with the shape of a pre-made gypsum model of the formed stump, and the frame is formed from gold-plated metal mesh with a mesh thickness of 0.4 mm, and before reconstruction / restoration of the crown part by applying composite material to the frame, the frame is mounted on a gypsum model and coated twice with a masking agent, the anatomical shape of the mesh-composite crown part is adjusted and fixed on cult through cement.